muck

American  

[muhk] / mʌk /

noun

1. moist farmyard dung, decaying vegetable matter, etc.; manure.

2. a highly organic, dark or black soil, less than 50 percent combustible, often used as a manure.

3. mire; mud.

4. filth, dirt, or slime.

5. defamatory or sullying remarks.

6. a state of chaos or confusion.

   to make a muck of things.

7. Chiefly British Informal. something of no value; trash.

8. (especially in mining) earth, rock, or other useless matter to be removed in order to get out the mineral or other substances sought.

---

verb (used with object)

1. to manure.

2. to make dirty; soil.

3. to remove muck from (sometimes followed byout ).

4. Informal.

   1. to ruin; bungle (often followed byup ).

   2. to put into a state of complete confusion (often followed byup ).

verb phrase

1. muck about / around to idle; waste time; loiter.

muck British  

/ mʌk /

noun

1. farmyard dung or decaying vegetable matter

2. Also called: muck soil.  an organic soil rich in humus and used as a fertilizer

3. dirt or filth

4. earth, rock material, etc, removed during mining excavations

5. slang rubbish

6. See Lord Muck Lady Muck

7. slang to ruin or spoil

---

verb

1. to spread manure upon (fields, gardens, etc)

2. to soil or pollute

3. (often foll by out) to clear muck from

Etymology

Origin of muck

1200–50; Middle English muc, muk < Old Norse myki cow dung

Explanation

Muck is a goopy, muddy substance, like the muck at the bottom of a pond or the muck you clean out of the gutters on your house once a year. You can also use muck to mean animal manure, its original, 13th-century meaning — specifically, "cow dung and vegetable matter used as manure." The definition has expanded since then to include any number of dirty, slimy substances, from the mud on the bottom of a lake to the sludge in a flooded basement. As a verb, to muck is either to remove animal waste or to spread manure on a field.

Example Sentences

If sweeping appeals to our collective empathy have failed to resonate—if the public is not moved by Randy Fine’s intersectional shortcomings—maybe we are better off getting down in the muck.

From Slate • Feb. 12, 2026

Even “when I’m in the mud and I have filled up my muck boots with mud and water, at no point have I ever thought, ‘Man I miss the office,’” he says.

From The Wall Street Journal • Feb. 7, 2026

“Like slime, sludge, and muck, slop has the wet sound of something you don’t want to touch,” the editors continued.

From Salon • Jan. 13, 2026

Somewhere in the muck of forgettable games against the likes of Boise State and Boston College and Navy, they needed a marquee win.

From Los Angeles Times • Dec. 7, 2025

I wanted him to go on talking like this, that his bitterness might loosen and come away, carrying with it all the pent-up hatred and disgust and muck of the lost years.

From "Rebecca" by Daphne du Maurier

Related Words

• dirt
• goo
• gunk
• manure
• mud
• slime
• sludge
• trash